CVE-2026-63385

Published: Ago 20, 2026 Last Modified: Ago 20, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,2
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has two HTTP parsing weaknesses in http.c. evhttp_decode_uri_internal decodes percent-encoded %00 bytes into literal NUL characters, which can cause downstream C string operations to truncate a path and bypass validation performed on a different representation. evhttp_header_is_valid_value also accepts obsolete line folding in header values containing carriage return or line feed characters, allowing a proxy and libevent to interpret headers differently and enabling header injection or access control bypass. The CRLF header acceptance is fixed in versions 2.1.13 and 2.2.2-alpha, but the reviewed patches do not clearly remediate the URI NUL-truncation condition.

444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Incomplete
Common Consequences
Security Scopes Affected:
Integrity Non-Repudiation Access Control
Potential Impacts:
Unexpected State Hide Activities Bypass Protection Mechanism
Applicable Platforms
Technologies: Web Based, Web Server
View CWE Details
https://github.com/libevent/libevent/commit/758be0c0f69c1934ef9a84ab39e9f9e5fde…
https://github.com/libevent/libevent/commit/9170dd35e64714613e8d13b290587cfc28e…
https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable
https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
https://github.com/libevent/libevent/security/advisories/GHSA-jcwh-pvf2-73p2